Unfortunately most toolboxes are not compatible with the Peragon cover. Our cover retracts down into the front of the bed. Conventional toolboxes placed next to the cab use the space our cover needs to operate. It is not possible to modify or customize our cover to work with these tool boxes.
Tool boxes that mount on rails in the floor of the bed that can be moved back may be compatible. If you're interested in a different type of tool box, consider the SwingCase brand.